Mayorga, who did his training in the Bronx, N.Y., said there is a "pretty brisk" population of people who use heroin in southeastern Connecticut and that they frequently go to the emergency room for treatment of infections related to injecting the drug and withdrawal.

"It feels like an inner-city ER quite often for not being a huge city," Mayorga said in a phone interview Thursday.

He suggested addicts whose drug suppliers have been arrested would first look for another source. He said they usually need to use the drug on a daily basis to avoid withdrawal.

Cocaine withdrawal is "not so much of an issue," Mayorga said.

"You come off it and sleep for a few days and get over it," he said.

Withdrawing from heroin is intense, he said, and users will experience vomiting, diarrhea and "skin-crawling."

"People usually say they feel like they are dying, but interestingly enough, it never kills you," he said. "You try to stay hydrated and stay away from other narcotics."

In the emergency room, patients in withdrawal are treated with anti-nausea drugs and given fluids, Mayorga said, and are encouraged to get into a detox program, such as Stonington Institute or the Southeastern Council on Alcoholism and Drug Dependence.

Officials from Stonington Institute declined to comment on the drug raids Thursday, and SCADD officials did not respond to a phone message.

Mayorga said he has not seen human drug couriers seeking medical treatment locally. Couriers usually wrap the drugs in condoms and use lubricants to swallow as many as they can, he said. Once they arrive at their destination, they wait for a bowel movement to retrieve the drugs.

If the condoms burst, "there's really not much room for intervention," Mayorga said.

"If you burst a certain amount of cocaine and heroin, you will die very quickly (of a drug overdose)," he said.